Electropolymerization from deep eutectic solvents (DES), a green alternative to room temperature ionic liquids, could be a convenient route to the fabrication of organic semiconductors at lower economic and environmental cost which has been barely studied in the literature. This work explores the novel use of choline-based solvents in the electrosynthesis of Polyaniline (PANI), a model conducting polymer. Different mixtures of choline chloride with ethylene glycol (Ethaline), glycerol (Glyceline), and urea (Reline) were prepared for these purposes. PANI was grown and characterized in-situ by Cyclic Voltammetry. Ex situ Scanning Electron Microscopy (SEM) unveiled the formation of dense matrices in the nanoscale from Ethaline and Glyceline but just a bunch of clusters from Reline. The large amounts of ionic and H bond donor species in these formulations, led to conductivities ten times higher than those for aqueous PANI (sigma approximate to 63 S . cm(-1)), great reversibility for the transitions between the different redox states of the polymer (indicating efficient charge transport and low amount of charge traps), and a limited stability toward continuous potential cycling in DES (associated to the increase in the water content). Nonetheless, the latter was significantly improved in aqueous media. More generally, the feasibility of electropolymerization processes using DES is demonstrated. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.059209jes] All rights reserved.